[plt-scheme] DrScheme and sound. Perhaps somebody did it.

From: Tim Hanson (tbhanson at gmx.de)
Date: Sun Oct 26 03:15:18 EST 2003

On Thursday, Oct 16, 2003, at 13:38 Europe/Berlin, Jerzy Karczmarczuk 
wrote [excerpt]:

> Boring numer crunching??
> But this is the point, sound generation may help to make it less 
> boring.
> * What is a spectrum? What *GIVES YOU* the Fourier transform of real 
> signals?
>   What information is stored in the phase? [Actually this is an awful 
> question]
> * All practice and algorithmics of filtering. Some recursive 
> algorithms are
>   very elegant, laziness may help to design IIR filters, etc. Doing it 
> in
>   "C" is disgusting...
> * Plenty of functional techniques. Composition of functions, e.g., 
> construction
>   and application of sound envelopes.
>   Higher-order functions for the parametrization, of pitch-shifting 
> (vibrato),
>   of automatic harmonic generation, of specific noise contributions, 
> etc.
>   Recursive algorithms for various effects: flanging, reverberation, 
> chorus,
>   and God knows what more...
> * Modular construction of *physical models* of sound generators. 
> Oscillators,
>   Karplus-Strong plucked strings, waveguides, you name it...
> =========
> A personal side remark.
> You know, some years ago I decided to teach Scheme without being 
> obliged to
> teach Scheme. So, I took an optional course for the second-year 
> students, and
> I began to teach computer graphics, 3D modelling (mainly parametric 
> surfaces),
> the rendering of 3D objects etc., very, very simple algorithms, and 
> toy problems
> not requiring huge computing power [I am not so naive as to try to 
> make a ray-
> tracer in Scheme...]. The students knew Scheme a little, but mainly 
> silly
> "pedagogical" surface, and trivial exercices. I put them to work on a 
> "real"
> application stuff and it worked very well.
> So, now I thought I'll do a similar thing, but with audio problems 
> instead of
> visual (they are not forgotten, it is always nice to plot some 
> spectra...)

i think these are very cool ideas. something like 12 years ago (in a 
math "Proseminar") i gave a talk on Fejér sums (something to do with 
Fourier series). I was learning TI Scheme at the time and to illustrate 
how certain series looked in the first few terms I used Scheme to graph 
some of them. Listening to what they "sounded" like would have been a 
fun alternative.

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